WO2020129111A1

WO2020129111A1 - Rotating electric machine

Info

Publication number: WO2020129111A1
Application number: PCT/JP2018/046282
Authority: WO
Inventors: 雄二白形; 健太藤井; 佐々木　大輔; 俊吾宮城; 矢原　寛之; 浩之東野; 潤田原
Original assignee: 三菱電機株式会社
Priority date: 2018-12-17
Filing date: 2018-12-17
Publication date: 2020-06-25
Also published as: CN113169622A; EP3902118A4; JP7109587B2; EP3902118A1; JPWO2020129111A1

Abstract

The present invention provides a rotating electric machine that can suppress expansion of the outer diameter of the rotating electric machine by mounting a power module and a heat sink. This rotating electric machine (100) comprises: a power module (160) provided with power semiconductor elements (166H, 166L) that turn on and off electrical conduction to a winding (32); a heat sink (110) that is thermally connected to a heat sink fixing surface (16) of the power module (160); and a refrigerant channel (180) through which refrigerant flows in a placement space of the heat sink (110), wherein the heat sink fixing surface (16) of the power module (160) extends in a radial direction (Y) and an axial direction (Z), and in the refrigerant channel (180), refrigerant flows in the radial direction (Y) in the placement space of the heat sink (110).

Description

Rotating electric machine

This application relates to a rotating electric machine.

The rotating electric machine includes a rotating electric machine main body including a rotor and a stator, and a power supply unit including an inverter that supplies electric power to the rotating electric machine main body and a control circuit. Due to space saving and ease of installation, and shortening of the wiring harness that connects the rotating electric machine main unit and the inverter, a rotating electric machine of the electro-mechanical integrated type that integrates the rotating electric machine main unit and the power supply unit has been developed. Being developed.

For example, in the rotary electric machines disclosed in Patent Document 1 and Patent Document 2, the inverter is attached to the end of the rotary electric machine. Fins are formed on the heat sink of the inverter, and cooling air generated by a blower fan attached to the end of the rotor passes through the fins to cool the inverter.

Japanese Patent Publication No. 2016-537959 JP, 2017-112807, A

However, in the technique of Patent Document 1, the heat sink of the power module and its fins extend in the circumferential direction and the radial direction, and the fins project in the axial direction. Therefore, the power module, the heat sink, and the fin are arranged so as to spread in the circumferential direction, and the arrangement area in the circumferential direction is large. Therefore, when mounting a plurality of power modules, there is a problem that the outer diameter of the power supply unit becomes large.

In the technique of Patent Document 2, the heat sink and the fins of the power module extend in the circumferential direction and the axial direction, and the fins protrude inward in the radial direction. Therefore, the power module, the heat sink, and the fin are arranged so as to spread in the circumferential direction, and the arrangement area in the circumferential direction is large. Therefore, when mounting a plurality of power modules, there is a problem that the outer diameter of the power supply unit becomes large.

Further, in the technique of Patent Document 2, it is necessary to allow the cooling air to flow in the axial direction near the rotating shaft, and therefore, in order to improve the cooling efficiency, an opening is provided at the axial end of the power supply unit. However, the arrangement of parts such as the control circuit is limited.

For example, when installing a rotating electrical machine in the engine room of a car, it is required to be able to install it in a limited space. When the outer diameter of the rotating electric machine is restricted, it is necessary to suppress the expansion of the outer diameter of the rotating electric machine by mounting the power module and the heat sink.

Therefore, there is a demand for a rotating electric machine that can suppress the expansion of the outer diameter of the rotating electric machine by mounting a power module and a heat sink.

The rotary electric machine according to the present application,
A stator with windings of multiple phases,
A rotor arranged radially inward of the stator,
A rotating shaft that rotates integrally with the rotor,
A bracket that accommodates the stator and the rotor and rotatably supports the rotation shaft,
A power module provided with a power semiconductor element for turning on and off the energization of the winding,
A heat sink thermally connected to the heat sink fixing surface of the power module,
A control circuit for controlling the power semiconductor element,
A refrigerant flow path through which a refrigerant flows in the heat sink arrangement space,
The heat sink fixing surface of the power semiconductor element extends in a radial direction and an axial direction of the rotating shaft,
In the coolant passage, the coolant flows in the radial direction in the heat sink arrangement space.

According to the rotating electric machine of the present application, the heat sink fixing surface of the power module extends in the radial direction and the axial direction, and the heat sink is arranged on one side or the other side in the circumferential direction of the heat sink fixing surface. Therefore, it is possible to prevent the power module and the heat sink from extending in the circumferential direction, and it is possible to suppress an increase in the circumferential arrangement area of the power module and the heat sink. Therefore, it is possible to prevent the outer diameter of the rotating electric machine from increasing due to the mounting of the power module and the heat sink.

FIG. 3 is a perspective view of the rotary electric machine according to the first embodiment. FIG. 3 is a cross-sectional view of the rotary electric machine according to the first embodiment, taken along a plane passing through the axis of the rotary shaft. FIG. 3 is a perspective view of one power module and heat sink according to the first embodiment. FIG. 3 is a circuit diagram of a power semiconductor element provided in one power module according to the first embodiment. FIG. 4 is a side view of the paired power modules and the heat sink according to the first embodiment as viewed from the outside in the radial direction. FIG. 6 is a cross-sectional view of the rotary electric machine according to Embodiment 2 taken along a plane passing through the axis of a rotary shaft. FIG. 9 is a cross-sectional view of a main part of the rotary electric machine according to Embodiment 3 taken along a plane passing through the axis of a rotary shaft. FIG. 9 is a cross-sectional view of a main part of the rotary electric machine according to Embodiment 3 taken along a plane passing through the axis of a rotary shaft.

Hereinafter, preferred embodiments of the rotating electric machine according to the present application will be described with reference to the drawings. In each figure, the same or corresponding parts will be described with the same reference numerals. It should be noted that in the drawings between the drawings, the size and scale of each corresponding component are independent.

1. Embodiment 1
The rotary electric machine 100 according to the first embodiment will be described with reference to the drawings. FIG. 1 is a perspective view of the rotary electric machine 100. FIG. 2 is a schematic cross-sectional view of the rotary electric machine 100 taken along a plane passing through the heat sink 110 and the axis C of the rotary shaft 4. FIG. 3 is a perspective view of one power module 160 and the heat sink 110. FIG. 4 is a circuit diagram of a power semiconductor element provided in one power module 160, and FIG. 5 is a side view of the power module 160 and the heat sink 110 as viewed from the radial outside Y2.

In the present application, a direction parallel to the axis C of the rotating shaft 4 is defined as an axial direction Z, and one side Z1 of the axial direction is referred to as a front side Z1. The other side Z2 is referred to as the rear side Z2. The radial direction Y and the circumferential direction X are the radial direction and the circumferential direction with respect to the axis C of the rotary shaft 4.

<Main body 200 of rotating electric machine>
The rotating electric machine 100 includes a rotating electric machine body 200. The rotating electric machine main body 200 includes a stator 3 provided with windings of a plurality of phases, a rotor 6 arranged on a radially inner side Y1 of the stator 3, a rotary shaft 4 which rotates integrally with the rotor 6, and a stator. 3 and the rotor 6, and a bracket that rotatably supports the rotating shaft 4 is provided.

In this embodiment, the bracket is composed of the front side bracket 1 on the front side Z1 and the rear side bracket 2 on the rear side Z2. The front bracket 1 has a cylindrical outer peripheral wall and a disk-shaped side wall extending radially inward Y1 from the front side Z1 end of the outer peripheral wall, and the rotary shaft 4 is provided at the center of the side wall. A through hole is provided through which the front bearing 71 is fixed. The rear bracket 2 has a cylindrical outer peripheral wall and a disk-shaped side wall extending inward in the radial direction Y1 from the rear side Z2 end of the outer peripheral wall, and the rotary shaft 4 is provided at the center of the side wall. A through hole is provided through which the rear bearing 72 is fixed. The front side bracket 1 and the rear side bracket 2 are connected by a bolt 15 extending in the axial direction Z.

The end of the rotary shaft 4 on the front side Z1 penetrates through the through hole of the front bracket 1 and projects further to the front side Z1 than the front bracket 1, and the pulley 9 is fixed to this projection. A belt is stretched between the pulley 9 and the pulley 9 fixed to the crankshaft of the engine (not shown), and the rotational driving force is transmitted between the rotary electric machine 100 and the engine.

The rear side Z2 end of the rotary shaft 4 penetrates the through hole of the rear side bracket 2 and projects to the rear side Z2 more than the rear side bracket 2, and a pair of slip rings 90 are provided on this protruding part. ing. The pair of slip rings 90 are connected to the field winding 62 of the rotor 6.

The rotor 6 includes a field winding 62 and a field iron core 61. The rotor 6 is of a Lundell type (also called a claw pole type). The field iron core 61 includes a cylindrical center portion, a front side claw portion extending from an end portion on the front side Z1 of the center portion to a radial outside Y2 of the center portion, and an end portion on the rear side Z2 of the center portion. And a rear side claw portion that extends to the outside Y2 in the radial direction of the center portion. The insulated copper wire of the field winding 62 is concentrically wound around the outer peripheral surface of the central portion of the field iron core 61. The front side claw portion and the rear side claw portion are alternately provided in the circumferential direction X, and have different magnetic poles. For example, the front side claw portion and the rear side claw portion are provided in six or eight, respectively.

The stator 3 is arranged so as to surround the rotor 6 with a minute gap, and has a cylindrical stator core 31 having slots, and a multi-phase winding wound around the slots of the stator core 31. 32, and. The plural-phase windings 32 are, for example, one set of three-phase windings, two sets of three-phase windings, one set of five-phase windings, or the like, and are set according to the type of the rotating electric machine.

The multi-phase winding 32 has a front coil end portion protruding from the stator core 31 to the front side Z1, and a rear coil end portion protruding from the stator core 31 to the rear side Z2. The lead wires of the multi-phase windings 32 penetrate the rear bracket 2 and extend to the rear Z2 (not shown).

　The front bracket 1 and the rear bracket 2 are provided with a gap in the axial direction Z. The stator core 31 is sandwiched between the opening ends on the rear side Z2 of the front bracket 1 and the opening ends on the front side Z1 of the rear bracket 2 from both axial ends.

A front side blower fan 81 having a plurality of blades is fixed to an end portion of the rotor 6 (field iron core 61) on the front side Z1, and a rear side Z2 end of the rotor 6 (field iron core 61) is fixed. Is attached with a rear side blower fan 82 having a plurality of blades, and they rotate integrally with the rotor 6. The front-side blower fan 81 and the rear-side blower fan 82 cool the front-side coil end portion, the rear-side coil end portion, and the like arranged on the radially outer side Y2.

The rear bracket 2 is provided with a plurality of openings 22 (hereinafter, referred to as exhaust openings 22) dispersed in the circumferential direction at a portion on the radially outer side Y2 of the rear blower fan 82. A plurality of openings 21 (hereinafter, referred to as intake openings 21) are provided in a portion dispersed in the circumferential direction.

<Power supply unit 300>
The rotating electric machine 100 includes a power supply unit 300 that supplies electric power to the rotating electric machine main body 200. The power supply unit 300 is arranged on the rear side Z2 of the rotary electric machine main body 200 and is fixed to the rotary electric machine main body 200. The power supply unit 300 includes a plurality of power semiconductor elements, includes an inverter that performs DC/AC conversion between a DC power supply and windings of a plurality of phases, and a control circuit 170 that controls ON/OFF of the power semiconductor elements. ing. In the present embodiment, the inverter is composed of the power module 160 provided with the power semiconductor element. The power supply unit 300 also includes a heat sink 110 that is thermally connected to the heat sink fixing surface 16 of the power module 160, and a coolant flow path 180 through which a coolant flows in the arrangement space of the heat sink 110.

The power supply unit 300 includes a pair of brushes that come into contact with a pair of slip rings 90 provided on a protruding portion of the rotary shaft 4 that protrudes from the rear bracket 2 to the rear side Z2, and a field via the brush and the slip ring 90. A power semiconductor element (not shown) for a field winding that turns on and off the power supplied to the winding 62. The power semiconductor element (switching element) for the field winding is on/off controlled by the control circuit 170. A rotation sensor 92 for detecting rotation information of the rotary shaft 4 is provided on the rear side Z2 of the rotary shaft 4. For the rotation sensor 92, a Hall element, a resolver, a magnetic sensor, an electromagnetic induction method, or the like is used.

The power supply unit 300 includes a cover 101. The cover 101 covers the rear side Z2 and the radially outer side Y2 of the control circuit 170, the power module 160, the heat sink 110, and the like. The cover 101 is formed in a bottomed tubular shape that opens to the front side Z1. The positive electrode power supply terminal 151 and the negative electrode power supply terminal 152 for connecting the inverter to the external DC power supply, and the control circuit 170 are connected to the external control device on the outer peripheral wall 101b of the cover 101 that covers the radially outer side Y2. A control connector 153 is provided for this purpose.

A cover opening 101c is provided on the outer peripheral wall 101b of the cover 101, and is open to the outside. No opening is provided in the rear side bottom wall 101a of the cover 101 that covers the rear side Z2. The front side Z1 of the cover 101 is open, and the opening is covered by the rotary electric machine main body 200 (rear side bracket 2).

The control circuit 170 includes a plate-shaped (disc-shaped in this example) circuit board 103. The control circuit 170 includes a case 102 that covers the circuit board 103. The circuit board 103 is composed of a printed board, a ceramic board, a metal board, or the like on which electronic components forming the control circuit 170 are mounted. In particular, since in-vehicle equipment requires high vibration durability, the circuit board 103 is fixed to the case 102 by screws, heat caulking, rivets, bonding, or the like. The fixed points are arranged at intervals of 50 to 60 mm, for example. This interval is an example, and may be changed according to the vibration condition and the product shape.

The circuit board 103 is arranged on the rear side Z2 of the rear side bracket 2 with a space. The circuit board 103 extends in the radial direction Y and the circumferential direction X. In the present embodiment, the surface of the circuit board 103 is orthogonal to the axial direction Z. The surface of the circuit board 103 may be inclined at an angle of, for example, 30 degrees or less with respect to the plane orthogonal to the axial direction Z. The case 102 covers the front side Z1 of the circuit board 103. The case 102 also includes a peripheral wall that covers the outer peripheral side of the circuit board 103. The rear side Z2 of the circuit board 103 is covered by the rear side bottom wall 101a of the cover 101.

The case 102 is provided with an opening (not shown) through which a control connecting member 164 of the power module 160 described later penetrates. The control connection member 164 is connected to the circuit board 103.

The rotary shaft 4 extends from the rear bracket 2 to the rear side Z2 from the front side Z1 surface of the circuit board 103 (immediately before the front side Z1 surface of the case 102 in this example). Therefore, the rotating shaft 4 does not penetrate the circuit board 103 and the case 102, and is arranged with a gap on the front side Z1 of the circuit board 103 and the case 102. According to this configuration, it is not necessary to provide the circuit board 103 and the case 102 with an opening for avoiding the rotation shaft 4. Therefore, the outer diameter of the circuit board 103 can be reduced, and the outer diameter of the power module 160 can be reduced in size and cost.

If the electronic components can be arranged within a range overlapping the rear bracket 2 in the axial direction Z, the circuit board 103 may be provided with a through hole through which the rotary shaft 4 penetrates. Further, the circuit board 103 does not have to have a disc shape as long as it fits within a range overlapping the rear bracket 2 in the axial direction Z, and may be composed of two or more circuit boards. The materials of the circuit board may be different.

The power supply unit 300 is connected to the positive side power semiconductor element 166H connected to the positive side of the DC power source and the negative side of the DC power source, as shown in FIG. 4, for one phase winding. One set of a series circuit in which the negative power semiconductor element 166L is connected in series is provided. A connection point where the positive power semiconductor element 166H and the negative power semiconductor element 166L are connected in series is connected to the winding of the corresponding phase. For example, three sets of series circuits are provided when one set of three-phase windings is provided, and six sets of series circuits are provided when two sets of three-phase windings are provided. Note that both or one of the positive and negative

power semiconductor elements

166H and 166L may be respectively configured by two or more power semiconductor elements connected in parallel.

Switching elements such as IGBT (Insulated Gate Bipolar Transistor) and power MOSFET (Power Metal Oxide Semiconductor Field Effect Transistor) are used for the power semiconductor element. These are used in inverters that drive devices such as motors, and control rated currents of several amps to several hundred amps. Silicon (Si), silicon carbide (SiC), gallium nitride (GaN), or the like may be used as the material of the power semiconductor element.

In the present embodiment, one power module 160 is provided with one series circuit of the positive power semiconductor element 166H and the negative power semiconductor element 166L. As shown in FIGS. 3 and 4, the power module 160 is connected to the positive electrode side connecting member 161 connected to the collector terminal of the positive power semiconductor element 166H and to the emitter terminal of the negative power semiconductor element 166L. The negative electrode side connecting member 162, the winding connecting member 163 connected to a connection point between the emitter terminal of the positive side power semiconductor element 166H and the collector terminal of the negative side power semiconductor element 166L, the positive side and And a control connection member 164 connected to the gate terminals and the like of the

power semiconductor elements

166H and 166L on the negative electrode side. For the positive electrode side connecting member 161, the negative electrode side connecting member 162, the winding connecting member 163, and the control connecting member 164, a metal such as copper or copper alloy having good conductivity and high thermal conductivity may be used. May be plated with a metal material such as Au, Ni or Sn. Further, the metal and plating materials of each terminal may be composed of two or more kinds. Note that one power module 160 may be provided with one power semiconductor element, or may be provided with three or more power semiconductor elements. The configurations of the connecting members and the like are changed according to the number of power semiconductor elements.

The positive electrode side connecting member 161 is connected to the positive electrode side wiring member connected to the positive electrode side power supply terminal 151, and the negative electrode side connecting member 162 is connected to the positive electrode side wiring member connected to the negative electrode side power supply terminal 152. The connection member 163 is connected to a winding wiring member connected to the winding of the corresponding phase, and the control connection member 164 is connected to the control circuit 170.

The power semiconductor element is bonded to the wiring pattern of the metal or ceramic substrate, the bus bar, etc. with a conductive material such as solder or silver paste. The metal substrate is made of a base material such as aluminum or copper. The ceramic substrate is made of alumina, aluminum nitride, silicon nitride or the like. The bus bar is made of iron, aluminum, copper or the like. The wiring pattern and bus bar are collectively referred to as a lead.

The power module 160 has a heat sink fixing surface 16 to which the heat sink 110 is thermally connected. In the present embodiment, the power semiconductor element is fixed to one surface of the metal substrate, ceramic substrate, bus bar or the like, and the other surface of the metal substrate, ceramic substrate, bus bar or the like constitutes the heat sink fixing surface 16. doing. The heat sink fixing surface 16 may be provided on the same side as the surface of the metal substrate, the ceramic substrate, the bus bar or the like to which the power semiconductor element is fixed. Further, the two surfaces of the power module 160 which are opposite to each other may be the heat sink fixing surfaces 16, and the heat sink 110 may be thermally connected to each surface.

In the present embodiment, a heat transfer material is interposed in the connection between the heat sink fixing surface 16 and the heat sink 110 in order to reduce the contact thermal resistance. In the case of a metal substrate or a ceramic substrate, a conductive or insulating material such as grease, an adhesive, a sheet or a gel, or a conductive member such as solder or silver paste is used as the heat transfer material. In the case of a lead that needs to be insulated from the heat sink 110, an insulating material is used as the heat transfer material. As a result, the power module 160 and the heat sink 110 are thermally connected via the heat transfer material, so that it is possible to reduce the number of members and bonding steps and reduce the thermal resistance.

When the leads and the heat sink 110 have the same potential, they may be connected by a conductive member such as solder, or the leads joined to the power semiconductor element are mechanically pressed against the heat sink 110 by springs or screws. May be. By changing from joining to mechanical pressing, deterioration in temperature cycle and high temperature is reduced while reducing thermal resistance, and long-term reliability is improved. Further, the heat sink 110 may be integrated into a module with the power module 160.

The power module 160 includes a sealing resin 165. The sealing resin 165 seals the power semiconductor element, the positive electrode side connecting member 161, the negative electrode side connecting member 162, the winding connecting member 163, the control connecting member 164, and other components. Examples of the sealing resin 165 include potting resins such as epoxy resin, silicone resin, urethane resin, coating materials for the surface of power semiconductor elements such as fluororesin, polybutylene terephthalate (PBT), polyphenylene sulfide (PPS), and polyether. A molding material such as ether ketone (PEEK) or acrylonitrile butadiene styrene (ABS) is used. By covering the components such as the power semiconductor element with the sealing resin 165, insulation can be ensured even when foreign matter is mixed in or when water containing salt, mud or the like is splashed. Further, by using a material having a high hardness such as epoxy resin, the parts can be fixed and the vibration resistance can be improved. The sealing resin 165 may be omitted as long as the power module 160 can be insulated and fixed by a method other than the sealing resin 165.

<Arrangement configuration of cooling mechanism>
The power module 160 and the heat sink 110 are arranged in the space between the rear bracket 2 and the circuit board 103 (in this example, the case 102) in the axial direction Z. The heat sink fixing surface 16 of the power module 160 extends in the radial direction Y and the axial direction Z. In the coolant channel 180, air as a coolant flows in the radial direction Y in the arrangement space of the heat sink 110. The refrigerant may be a medium other than air (for example, cooling water).

According to this configuration, the heat sink fixing surface 16 of the power module 160 extends in the radial direction Y and the axial direction Z, and the heat sink 110 is arranged on one side or the other side of the heat sink fixing surface 16 in the circumferential direction X. .. Therefore, it is possible to suppress the power module 160 and the heat sink 110 from extending in the circumferential direction X, and it is possible to suppress an increase in the layout area of the power module 160 and the heat sink 110 in the circumferential direction X. Therefore, it is possible to prevent the outer diameter of the power supply unit 300 from increasing due to the mounting of the power module 160 and the heat sink 110.

The heat sink 110 is arranged on one side or the other side of the heat sink fixing surface 16 in the circumferential direction X. Since the coolant flow path 180 through which the coolant flows in the radial direction Y is provided in the arrangement space of the heat sink 110, the space between the rear bracket 2 and the circuit board 103 arranged at intervals in the axial direction Z is provided. The coolant flow channel 180 can be provided by utilizing it. Therefore, it is not necessary to reduce the layout area of the circuit board 103 in order to flow the refrigerant to the rear side Z2 of the power module 160. Further, since the refrigerant flows in the radial direction Y, the refrigerant can pass near the protrusion on the rear side Z2 of the rotating shaft 4 on the radially inner side Y1. Therefore, the slip ring 90 and the brush, the rotation sensor 92, and the rear bearing 72, which are provided near the protrusion on the rear side Z2 of the rotary shaft 4, can also be efficiently cooled.

In the present embodiment, the heat sink fixing surface 16 is a flat surface and extends along a plane passing through the axis C. The heat sink fixing surface 16 may have irregularities or a curved surface as long as it extends in the radial direction Y and the axial direction Z. Further, the heat sink fixing surface 16 may be inclined at an angle of, for example, 30 degrees or less with respect to a plane passing through the axis C and intersecting with the heat sink fixing surface 16.

In the present embodiment, the power module 160 is formed in a rectangular parallelepiped shape, and each of the connecting members 161 to 164 projects from the rectangular parallelepiped portion. The heat sink fixing surface 16 is one surface of a rectangular parallelepiped. Each side of the rectangular parallelepiped is arranged so as to be parallel or orthogonal to the axial direction Z. The width of the power module 160 in the circumferential direction X is smaller than the width in the radial direction Y and the width in the axial direction Z. In addition, each side of the rectangular parallelepiped may be arranged so as not to be parallel or orthogonal to the axial direction Z but to be inclined. Further, the power module 160 may be formed in a shape other than the rectangular parallelepiped shape.

The control connecting member 164 projects from the rear side Z2 surface of the power module 160 to the rear side Z2, and is connected to the circuit board 103 arranged on the rear side Z2 of the power module 160. The positive electrode side connecting member 161, the negative electrode side connecting member 162, and the winding connecting member 163 protrude from the surface of the power module 160 opposite to the heat sink fixing surface 16.

The heat sink 110 is thermally connected to the heat sink fixing surface 16 of the power module 160. The heat sink 110 is arranged on one side or the other side of the heat sink fixing surface 16 in the circumferential direction X. The heat sink 110 has a role of radiating the heat generated when a current flows through the power semiconductor element and the conduction path and the heat coming from other components to the outside. The heat sink 110 is configured using a material having a thermal conductivity of 5 W/m·K or more, such as metal such as aluminum, aluminum alloy, copper, and copper alloy, ceramic, resin, or the like.

The heat sink 110 extends in the radial direction Y and the axial direction Z, and is a plate-shaped base portion 110a that is thermally connected to the heat sink fixing surface 16, and protrudes from the base portion 110a to the side opposite to the heat sink fixing surface 16. It has a plurality of protrusions 110b. The heat dissipation area can be increased by providing the plurality of protrusions 110b. In the present embodiment, each of the plurality of protrusions 110b is formed in a plate shape that extends in the circumferential direction X and the radial direction Y at intervals in the axial direction Z. In the present embodiment, the plurality of plate-shaped protrusions 110b are flat plates that extend in parallel to the circumferential direction X and the radial direction Y. In addition, the plurality of plate-shaped protrusions 110b need only extend in the circumferential direction X and the radial direction Y, and with respect to a plane parallel to the circumferential direction X and the radial direction Y (a plane orthogonal to the axial direction Z). For example, it may be inclined at an angle within 30 degrees.

The base 110a is formed in a rectangular parallelepiped shape having a surface having an area equal to that of the heat sink fixing surface 16 of the power module 160. The width of the base portion 110a in the circumferential direction X is shorter than the width in the radial direction Y and the width in the axial direction Z. The protrusion 110b is formed in a rectangular flat plate shape. Note that the base portion 110a may be formed in a shape other than a rectangular parallelepiped shape as long as it has a surface fixed to the heat sink fixing surface 16, and the protrusion 110b is formed in a plate shape other than a rectangular flat plate shape. May be. Further, if heat dissipation can be ensured, the heat sink 110 may not be provided with the plurality of protrusions 110b.

The width of the entire outer shape of the power module 160 and the heat sink 110 excluding the connecting members in the circumferential direction X is shorter than the width in the radial direction Y and the width in the axial direction Z. Therefore, by disposing the heat sink fixing surface 16 so as to extend in the radial direction Y and the axial direction Z, the arrangement area of the power module 160 and the heat sink 110 in the circumferential direction X can be reduced.

In the present embodiment, as shown in FIG. 5, the power module 160 is arranged so that the heat sink fixing surface 16 faces one side in the circumferential direction X. Then, the heat sink 110 is fixed to one side of the heat sink fixing surface 16 in the circumferential direction X, and a refrigerant flow channel 180 through which air as a refrigerant flows in the radial direction Y is formed on one side of the heat sink 110 in the circumferential direction X. .. In FIG. 5, the right side is the one side in the circumferential direction X and the left side is the other side in the circumferential direction X. The power module 160 may be arranged with the heat sink fixing surface 16 facing the other side in the circumferential direction X, or the heat sink 110 may be fixed to the other side of the heat sink fixing surface 16 in the circumferential direction X.

A cover opening 101c is provided in the portion of the cover 101 on the radially outer side Y2 of the heat sink 110. Therefore, the air as the refrigerant can be concentratedly flown to the flow path on one side in the circumferential direction X of the heat sink 110, and the cooling efficiency can be improved. A plurality of cover openings 101c may be provided according to the number of heat sinks 110 and power modules 160.

In the present embodiment, as shown in FIG. 5, the opening area of the cover opening 101c is an area corresponding to the arrangement area of the heat sink 110. In order to reduce the gap between the cover opening 101c and the heat sink 110 and the power module 160, the end faces of the heat sink 110 and the power module 160 on the radially outer side Y2 should be equal to the radial position of the cover opening 101c. It is arranged. Therefore, the air can efficiently flow through the flow path on one side in the circumferential direction X of the heat sink 110.

As shown in FIG. 2, the case 102 is arranged on the rear side Z2 of the arrangement space of the heat sink 110, and the rear bracket 2 is arranged on the front side Z1 of the arrangement space of the heat sink 110. And the cooling efficiency can be improved.

In the present embodiment, as shown by the arrow in FIG. 2, in the coolant flow path 180, air as a coolant passes through the cover opening 101c of the cover 101 and is sucked from the outside, and then the space for disposing the heat sink 110 is changed. It flows to the inside Y1 in the radial direction. The air may flow in the opposite direction.

When a metal material is used for the cover 101, external noise is reflected or absorbed to reduce the influence on the power supply unit 300, and noise emitted from the power supply unit 300 is reflected or absorbed to the peripheral devices. The impact can be reduced.

2. Embodiment 2
Next, the rotary electric machine 100 according to the second embodiment will be described. The description of the same components as those in the first embodiment is omitted. FIG. 6 is a schematic sectional view of rotary electric machine 100 according to the present embodiment, taken along a plane passing through heat sink 110 and axis C of rotating shaft 4.

In the present embodiment, as shown in FIG. 6, rotating electric machine 100 includes flow path forming member 104 that forms refrigerant flow path 180, and flow path forming member 104 includes power module 160 in axial direction Z and It is arranged between the heat sink 110 and the rear bracket 2.

According to this configuration, since the flow path forming member 104 is arranged on the front side Z1 of the arrangement space of the heat sink 110, the refrigerant can be collected in the arrangement space of the heat sink 110, and the cooling efficiency can be improved.

In the present embodiment, the flow path forming member 104 is formed in a plate shape extending in the radial direction Y and the circumferential direction X, and is formed in a region including the region where the heat sink 110 is arranged when viewed in the axial direction Z. It is arranged. Further, the flow path constituent member 104 is arranged so as to cover a part of the rear side Z2 of the rear bracket 2 on the rear side Z2 of the intake opening 21. According to this configuration, it is possible to prevent the refrigerant from being sucked into the intake opening portion 21 before reaching the end portion on the radially inner side Y1 of the arrangement space of the heat sink 110. Even if a part of the intake opening 21 is covered, the refrigerant flows through the intake openings 21 distributed in the circumferential direction X, so that the flow is not significantly hindered.

In addition, when the refrigerant sufficiently passes through the refrigerant flow path 180 and the heat dissipation property of the heat sink 110 can be sufficiently ensured, the flow path forming member 104 includes the rear side Z2 of the rear bracket 2 on the rear side Z2. May be arranged so as not to cover. In this case, the pressure loss generated in the refrigerant flow channel 180 can be reduced, and the flow rate of the refrigerant passing through the refrigerant flow channel 180 can be increased. Further, the flow path forming member 104 may have holes.

3. Embodiment 3
Next, rotary electric machine 100 according to the third embodiment will be described. The description of the same components as those in the first embodiment is omitted. 7 and 8 are schematic cross-sectional views of the rotary electric machine 100 according to the present embodiment taken along a plane passing through the heat sink 110 and the axis C of the rotary shaft 4.

In the present embodiment, as shown in FIGS. 7 and 8, as in the second embodiment, rotating electric machine 100 includes flow path forming member 104 that forms refrigerant flow path 180. 104 is arranged between the power module 160 and the heat sink 110 in the axial direction Z, and the rear bracket 2.

However, in the present embodiment, the flow path component 104 supports the power module 160 and the heat sink 110 from the front side Z1, and the support surface of the flow path component 104 is with respect to the portion on the radially inner side Y1. The portion on the radially outer side Y2 projects to the rear side Z2. Therefore, the power module 160 and the heat sink 110 are arranged so as to be inclined with respect to the radial direction Y so as to move to the front side Z1 as they go toward the radial inside Y1.

According to this configuration, in the arrangement space of the heat sink 110, the refrigerant moves to the front side Z1 as it moves radially inward Y1, so that the front side passes through the intake opening 21 on the rear side Z2 of the rear bracket 2. The pressure loss of the refrigerant flowing through Z1 can be reduced. Thereby, the flow rate of the refrigerant can be increased and the cooling efficiency can be improved.

Further, each of the plurality of plate-shaped protrusions 110b is inclined with respect to the radial direction Y so as to move to the front side Z1 as it goes toward the radial inside Y1. According to this configuration, the refrigerant can flow along the plate-shaped protrusion 110b inclined to the front side Z1, so that the pressure loss of the refrigerant flowing to the front side Z1 can be reduced more reliably.

The inclination of the plate-shaped protrusion 110b, the power module 160, and the heat sink 110 with respect to the radial direction Y is set within the range of 0 to 30 degrees (for example, 20 degrees). Note that the inclination of the plate-shaped protrusion 110b with respect to the radial direction Y and the inclination of the power module 160 and the heat sink 110 with respect to the radial direction Y do not have to be at the same angle. For example, the inclination of the plate-shaped protrusion 110b may be larger than the inclination of the power module 160 and the heat sink 110. Alternatively, the power module 160 and the heat sink 110 may not be tilted in the radial direction Y, and only the plate-shaped protrusion 110b may be tilted in the radial direction Y.

As shown in FIG. 7, the flow path forming member 104 includes a plate-shaped portion 104a that extends in the radial direction and the circumferential direction, and a protruding portion 104b that protrudes to the rear side Z2 from a portion on the radially outer side Y2 of the plate-shaped portion 104a. And may have. Alternatively, as shown in FIG. 8, the flow path forming member 104 has a plate-shaped portion 104a extending in the radial direction and the circumferential direction, and a rear side Z2 protruding from the plate-shaped portion 104a toward the inner side Y1 in the radial direction. It may have a triangular prism-shaped inclined portion 104c whose height gradually decreases. The flow path forming member 104 may have any shape as long as it can tilt and support the power module 160 and the heat sink 110, and may be composed of a single member or a plurality of members.

Although the present application describes various exemplary embodiments and examples, various features, aspects, and functions described in one or more of the embodiments apply to the particular embodiment. However, the present invention is not limited to this, and can be applied to the embodiments alone or in various combinations. Therefore, innumerable variations not illustrated are envisioned within the scope of the technology disclosed herein. For example, it is assumed that at least one component is modified, added or omitted, and at least one component is extracted and combined with the components of other embodiments.

1 front side bracket, 2 rear side bracket, 3 stator, 4 rotating shaft, 6 rotor, 16 heat sink fixing surface, 32 windings, 100 rotating electric machine, 101 cover, 101c cover opening (opening), 102 case, 103 circuit board, 104 flow path constituent member, 110 heat sink, 110a base part, 110b protruding part, 160 power module, 166H, 166L power semiconductor element, 170 control circuit, 180 refrigerant flow path, 200 rotating electric machine main part, 300 power Supply unit, C axis, X circumferential direction, Y radial direction, Y1 radial direction inside, Y2 radial direction outside, Z axial direction, Z1 front side (one side in axial direction), Z2 rear side (other side in axial direction)

Claims

A stator with windings of multiple phases,
A rotor arranged radially inward of the stator,
A rotating shaft that rotates integrally with the rotor,
A bracket that accommodates the stator and the rotor and rotatably supports the rotation shaft,
A power module provided with a power semiconductor element for turning on and off the energization of the winding,
A heat sink thermally connected to the heat sink fixing surface of the power module,
A control circuit for controlling the power semiconductor element,
A refrigerant flow path through which a refrigerant flows in the heat sink arrangement space,
The heat sink fixing surface of the power semiconductor element extends in a radial direction and an axial direction of the rotating shaft,
A rotating electric machine in which the refrigerant flows in a radial direction in the coolant flow path in the coolant flow path.
The control circuit includes a plate-shaped circuit board, the circuit board is arranged on the other side in the axial direction of the bracket with a space, and extends in the radial direction and the circumferential direction of the rotating shaft,
The rotary electric machine according to claim 1, wherein the power module and the heat sink are arranged in a space between the bracket and the circuit board in the axial direction.
The rotating electric machine according to claim 2, wherein the rotating shaft extends from the bracket to a surface on one side in the axial direction of the circuit board and on the other side in the axial direction.
The rotation according to claim 2 or 3, wherein the control circuit includes a case that covers one side in the axial direction of the circuit board, and a surface on one side in the axial direction of the case forms a flow path through which the refrigerant flows. Electric machinery.
Further comprising a cover for covering the power module and the control circuit,
The rotary electric machine according to any one of claims 1 to 4, wherein the cover is provided with at least one opening through which the refrigerant flows.
Further comprising a flow path forming member forming the refrigerant flow path,
The rotary electric machine according to any one of claims 1 to 5, wherein the flow path forming member is arranged between the power module and the heat sink and the bracket in an axial direction.
The flow path forming member supports the power module and the heat sink from one side in the axial direction,
The support surface of the flow path forming member, with respect to the radially inner portion, the radially outer portion is projected to the other side in the axial direction,
The rotating electric machine according to claim 6, wherein the power module and the heat sink are arranged so as to be tilted with respect to the radial direction so as to move to one side in the axial direction toward the inner side in the radial direction.
The heat sink has a plate-shaped base portion that extends in the radial direction and the axial direction and is fixed to the heat sink fixing surface, and a plurality of protruding portions that protrude from the base portion to the side opposite to the heat sink fixing surface. The rotating electric machine according to claim 1, wherein the rotating electric machine is provided.
The rotating electric machine according to claim 8, wherein each of the plurality of projecting portions is formed in a plate shape that extends in the circumferential direction and the radial direction at a distance from each other in the axial direction.
The rotary electric machine according to claim 9, wherein each of the plurality of protrusions is inclined with respect to the radial direction so as to move to one side in the axial direction as it goes inward in the radial direction.